Transition type couplers for railway vehicles



July 1968 OM PRAKASH TANTIA 3,

TRANSITION TYPE COUPLERS FOR RAILWAY VEHICLES Filed March 1, 1966 2Sheets-Sheet 1 Inventor 0M PHAKASH TANTIA A Home y y 9, 1968 OM PRAKASHTANTIA 3,39

TRANSITION TYPE COUPLERS FOR RAILWAY VEHICLES Filed March 1, 1966 2Sheets-Sheet 2 Inventor 0M PRAKASH TANTIA A Home y United States Patent3,391,800 TRANSITION TYPE COUPLERS FGR RAILWAY VEHICLES Om Prakash Tantia, 4 Sarat Chatterjee Ave., Calcutta 29, India Filed Mar. 1, 1966,Ser. No. 530,992 13 Claims. (Cl. 213-112) ABSTRACT OF THE DISCLOSURETransition type couplers using a clevis and screw coupler wherein theclevis has formed near the free end of the clevis shank a ledge or ridgewhich extends around the shank substantially along the bearing surfaceof the bow shackle with the said shank, and has a shoulder formed on atthe opposite end of the shank and part of the bearing surface on theshank between the said shoulder and said ledge is recessed.

Prior art Certain railway systems have still in use draw bar hook typeof couplings with side buffers. With the advancement of railroadengineering, it has been found that automatic centre buffer couplers aremore satisfactory for purposes of coupling two railway vehicles. Due toincrease in horsepower of locomotives, it has also become possible tohaul larger trains which necessitates greater draw bar pull to beexerted on the railway vehicle couplings.

Transition type couplers are used where the existing rail vehicleshaving the draw bar hooks are to be coupled to newly introduced centrebuffer couplers. The object of the transition coupler therefore is topermit vehicles with centre bufier couplers to be coupled to each otherand also to permit coupling of the same with vehicles having draw barhooks.

In the known centre buffer couplers, there is provided a clevispivotally mounted in a jaw on the said coupler and this coupler isrendered transition type by the provision of a screw coupling. The termscrew coupling is used to designate a coupling comprising a bow shacklewhich engages the clevis and a second shackle which engages the draw barhook, both shackles being connected by a threaded spindle. The clevisprovides the required bridge at the knuckle head of the centre buffercoupler and holds the bow shackle in a centrally located positionwhereby the draw bar forces pass through the centre line of the saidcoupler. In the locked position, a profile on the clevis mates with adepression on the knuckle head. This ensures that once the clevis andthe knuckle head are locked in position, there is practically norelative vertical movement between the two.

The difiiculty arises when due to improper locking of the knuckle headwith the clevis, the knuckle head which is pivotally mounted opens outand the bow shackle slips off the clevis. The second shackle beingengaged by the draw hook can easily slip off resulting in loss of thescrew coupling. To prevent the bow shackle from slipping off, lugs werewelded on the clevis after the bow shackle was slipped on. In the cleviswith these lugs the bow shackle could not slip ofiF. However, it hasbeen found that in the yards, the line staff do not lock the clevisproperly but leave the clevis loose in relation to the knuckle head.They only couple the screw coupling to the draw hook of the othervehicle. Under these conditions, when the train is pulled, the forcesexerted by the shackle against the welded lugs tend to damage these lugswhich lugs in many cases give way, thus causing the screw coupling toslip ofl.

3,391,800 Patented July 9, 1968 Objects of the invention The principalobject of this invention is to so modify the clevis that the aforesaiddisadvantages are eliminated. It is another object of this invention toso modify the clevis that without impairing its strength, its weight isreduced.

The invention According to this invention in a transition type coupleremploying a clevis and screw coupler, near the free end of the clevisshank is formed a ledge or ridge which extends around the shanksubstantially along the bearing surface of the bow shackle with the saidshank, while at the opposite end of the said shank is formed a shoulderand a part of the bearing surface on the shank between the said shoulderand said ledge is recessed.

According to another feature of this invention the ridge terminates ateach of its ends in a nose and the noses thus formed provide inconjuction with the said shoulder, diagonal constrictions for the bowshackle in engagement with the clevis shank, in a position, when theclevis is not in engagement with the knuckle of the coupler and the saidclevis is pulled with the shackle,

Further the inner face of the ledge is inclined such that when theknuckle is engaging the clevis, the shackle has the necessary free playin the said recess of the shank, but when the knuckle is not engagingthe clevis, and is pulled by the shackle, then by virtue of the inclinein the ridge, the noses of the said ridge come into engagement with thebow shackle and in cooperation with the shoulder prevent the clevis fromadopting a position substantially different from that when the saidclevis was held by the said knuckle.

According to another embodiment the head at the end of the clevis shankis provided on its cooperating surface with a ridge or the like having acontour which cooperates with the knuckle and pushes or kicks it intolocked position so that by rotating the clevis, locking is not onlyfacilitated but automatically effected and the bow shackle can adopt aposition suitable for engagement with the draw hook when the clevis islocked in position. The advantage of this modification is that when theclevis is rotated it must get locked before the bow shackle is ready forengagement with the draw bar hook.

In order to facilitate the rotation of the clevis a vertical rod issecured thereto which helps in the rotational movement of the cleviswhen the bow shackle is in suspended position.

Instead of having a ridge for kicking the knuckle, it is also possibleto so shape the contour of the head of the clevis that the entire headacts to kick or force the knuckle into locking position.

According to a further embodiment, the bearing surface of the shank ofthe clevis is so shaped that it holds the bow shackle to constrict itsangular movement, whereby the bow shackle is prevented from being freeto adopt any other position which is normal to the clevis shank. Forthis purpose it is preferred to provide a shoulder on the cleviscorresponding to the shoulder at the end of the clevis shank to bear oneither side of the bow shackle, when the bow shackle is engaged by theclevis.

According to a further embodiment a projection is provided on the frontportion of the clevis shank, the function of which is to prevent thescrew coupling from being hooked on to the draw hook when the clevis isin the fully opened or idle position by either the screw coupling beinglifted in a clockwise direction in this position or by rotating the samein reverse direction over about 270.

According to a further feature, the ridge which extends .all around orsubstantially encircles the clevis has been modified. At the nose thesaid ridge has been extended so that the nose position extends morebelow the clevis shank than the shoulder. In other words the outer endof the nose portion is made father away from the centre line of theclevis shank than the shoulder portion.

Describin gthe funcion of the above embodiment when the clevis isbrought into the use and is about parallel with the track, the screwcoupling is prevented from be ing lifted for coupling on to the drawhook and this is done by increasing the height of the ridge which inthis position is disposed at the lower side of the clevis shank.

Other features of the invention will be clear from the drawings and thedescription therefor.

The invention will now be more fully described with reference to theaccompanying drawings in which:

FIG. 1 is a side view of one clevis embodiment of the invention.

FIG. 2 is a cross-section of FIG. 1 taken along the line A'A'.

FIG. 3 is a perspective view of the clevis of FIG. 1.

FIG. 4 is a plan view of a transition coupler of the invention with theclevis of FIG. 1.

Referring to the drawings A shows the shank of the clevis, B itsendwhich is to be pivoted to the jaw of the centre buffer coupler C by apin D passing through the pin hole E.

According to this invention, near the free end of the clevis shank isformed a ridge R which extends around the shank A substantially alongthe bearing surface defined by the contact of the bow shackle F while inengagement with the said shank. At the end of the shank opposite theridge R is formed a shoulder S such that the bearing surface between thesaid shoulder and said ridge is recessed as more clearly seen byreference to FIG. 1 of the drawings and marked T. This recessed portionas will be seen from FIG. 1 is only in the upper bearing surface definedby the contact of the bow shackle with the shank. The section of theshank is so made that the loop of the bow shackle is generally bearingagainst this recessed surface.

The ridge may extend, all around the shank of the clevis but at any rateit must extend to substantially encircle the clevis, whereby at each endwhere the ridge terminates a nose N is formed. This nose functions incoopration with the shoulder S and it provides diagonal constrictionsfor the bow shackle. This will be apparent from FIG. 1 in which theposition of the bow shackle while engaging the clevis shank isillustrated. This position shown in dotted lines is assumed by the bowshackle when the clevis is not in engagement with the knuckle of thecoupler and the clevis is pulled with the shackle.

The ridge may conveniently extend right along the girth of the shank.

According to another feature the inner face R of the ridge is inclinedsuch that when the knuckle is engaging the clevis, the shackle has thenecessary play along the recessed portion of the shank, but when theknuckle is not engaging the clevis and is pulled by the shackle then byvirtue of the inclined face of the ridge the two noses M of the saidridge comes into immediate engagement with the arms of the bow shackleand in cooperation with the shoulder S prevent the clevis from adoptinga position different from that when the clevis was held by the knuckle.

According to another feature of this invention, the free end of theshank A has a female contour marked U which is complementary to a malecontour V on the knuckle.

According to another feature an are shaped lug L is provided on theclevis around the pin hole E to engage a female depression in thecoupler head, said lug having an arc subtending an angle of over 120whereby when the bow shackle is to be initially slipped over the clevistheclevis is turned through about 90 and after the shackle rests inposition against the ridge, the said clevis is turned back in a positionwhere the lug engages the depression in the coupler.

From FIG. 4 it will be seen that the clevis is engaged by a pin betweenthe jaws of the centre buffer coupler marked P and in the workingposition the said clevis is held and locked by the knuckle head'K, thebow shackle engaging the clevis and the second shackle engaging the drawbar hook W of a vehicle not having a transition coupling.

In the improved design the dimensions of the pin and of the clevis inrelation to the shackle are such that the shackle can he slipped on fromthe said end. The arc shaped lug also does not prevent the shackle frombeing slipped on. The clevis can then be assembled into the existingcoupler and the pin pushed through. Due to the provision of the ridgethe shackle is prevent from slipping off. In the event of the lockbetween the knuckle and the clevis opening out, the shackle of the screwcoupling resting against the noses and the shoulder when pulled willcause sideways forces on the ridge R which will prevent the clevis frommoving very much out of its alignment which would otherwise occur by theopening out of the knuckle. Thus, it will be seen that by the provisionof this ridge R not only has the slipping off of the shackle beenprevented but also the misalignment of the shackle and its displacementfrom the central position when draw forces are exerted has also beenminimised and thus the traction forces continue to act almost centrally.

Further improvement is that the female profile now provided at the endof the clevis mates exactly with the male profile of the knuckle. Theadvantage gained by this is derived from the fact that this end of theclevis having already been made dimensionally large there is matingacross considerable lengths of exact profiles between the clevis withits counterpart on the knuckle.

A further improvement found in the clevis according to this invention isthat the section at face X is kept to a minimum as compared to theoriginal clevis, thereby reducing considerably the weight of thecasting. In so doing, the recessed portion not only helps to reduce thesize and the weight of the clevis but also permits the screw coupling tobe shortened :by an equivalent length as compared to the existing screwcoupling. Here again the reduction in weight of the screw coupling isalso caused.

The total minimum angle of the arc shaped lug is so devised that even ifthe lock of the knucklehead with the clevis opens out and the shackledisplaces the clevis to the maximum extent possible, a considerableportion of the arc of the male lugs continue to mate with itscounterpart in the couplerhead casting. This ensures that even in theopen position of the knucklehead, the pin of the clevis is not undulystrained since the mating lugs continue to provide sufficient support tothe clevis preventing angular displacement in the plane of the verticalaxis of the pin.

I claim:

1. In and for transition type coupler employing .a clevis and screwcoupler, a clevis characterized by that near the free end of the clevisshank is formed a ledge or ridge which extends around the shanksubstantially along the bearing surface of the bow shackle with the saidshank, while at the opposite end of the said shank is formed a shoulderand that a part of the bearing surface on the shank between the saidshoulder and said ledge is recessed, said ridge terminating at each ofits ends in a nose and the noses thus formed providing in conjunctionwith the said shoulder, diagonal constrictions for the bow shackle inengagement with the clevis shank in position, when the clevis is not inengagement with the knuckle of the coupler and the said clevis is pulledwith the shackle.

2. In and for a transition type coupler a clevis as claimed in claim 1in which the inner face of the ledge is inclined such that when theknuckle is engaging the clevis, the shackle has the necessary free playin the said recess of the shank, but when the knuckle is not engagingthe clevis, and is pulled by the shackle, then by virtue of the inclinein the ridge the noses of the said ridge come into engagement with thebow shackle and in cooperation with the shoulder prevent the clevis fromadopting a position substantially different from that when the saidclevis was held by the said knuckle.

3. A transition type coupler employing a clevis of the type claimed inclaim 2 in which the shackle opening in relation to the clevis is suchthat it can he slipped on the clevis only from that end of the cleviswhich is pivotally connected but not through the free end.

4. A transition type coupler as claimed in claim 3 in which the free endof the clevis has a female engaging contour complementary to the maleengaging contour on the knuckle.

5. A transition type coupler as claimed in claim 2 in which an areshaped lug is provided on the clevis around its pin hole to engage afemale depression in the coupler head, said lug having an arc subtendingan angle of over 120, and being of dimensions as to permit the bowshackle to slip over to the shank.

6. A clevis as claimed in claim 1 in which the ridge or ledge extendsall around the shank of the said clevis.

7. A transition type coupler as claimed in claim 1 characterized in thehead at the end of the clevis shank is provided on its cooperatingsurface with a ridge or the like having a contour which cooperates withthe knuckle and pushes or kicks it into locked position so that byrotating the clevis, locking is not only facilitated but automaticallyeffected and the bow shackle can adopt a position suitable forengagement with the draw hook when the clevis is locked in position.

8. A coupler as claimed in claim 7 in which in order to facilitate therotation of the clevis a vertical rod is secured thereto which helps inthe rotational movement of the clevis when the bow shackle is insuspended position.

9. A coupler as claimed in claim 7 in which instead of having a ridgefor kicking the knuckle, it is also possible to so shape the contour ofthe head of the clevis that the entire head acts to kick or force theknuckle into locking position.

10. A transition type coupler as claimed in claim 1 wherein the bearingsurface of the shank of the clevis is so shaped that it holds the bowshackle to constrict its angular movement whereby the bow shackle isprevented from being free to adopt any other position which is normal tothe clevis shank.

11. A coupler as claimed in claim 10 in which a shoulder is provided onthe clevis corresponding to the shoulder at the end of the clevis shankto bear on either side of the bow shackle, when the bow shackle isengaged by the clevis.

12. A coupler as claimed in claim 10 in which a projection is providedon the front portion of the clevis shank which prevents the screwcoupling from being hooked on to the draw hook when the clevis is in thefully opened or idle position by either the screw coupling being liftedin a clockwise direction in this position or by rotating the same inreverse direction over about 270.

13. A coupler as claimed in claim 12 in which the ridge is so modifiedthat at the nose the said ridge has been extended so that the noseposition extends more below the clevis shank than the shoulder wherebythe nose portion is made farther away from the centre line of the clevisshank than the shoulder portion.

References Cited UNITED STATES PATENTS 1,599,038 9/1926 Bush 213-1l21,927,268 9/1933 Kinne 213-112 2,973,872 3/1961 Cope 213-112 DRAYTON E.HOFFMAN, Primary Examiner.

